A person who as undergone E therapy, and achieved the frontal lobe of their dreams.

In the future Earth of the novel, if you wanted to be smarter, you could actually grow more
brainier. Special genetic tampering called E Therapy could give anyone a huge frontal lobe.

The man's head reminded Hnatt of a photograph he had once seen in a textbook; the photo had been labeled hydrocephalic. The same enlargement above the browline; it was clearly domelike and oddly fragile-looking and he saw at once why these well-to-do persons who had evolved were popularly called bubbleheads. Looks about to burst, he thought, impressed. And -- the massive rind. Hair had given way to the darker, more uniform pattern of chitinous shell. Bubblehead?

Unfortunately, the process sometimes resulted in an irreversible loss of brain function. But,
by and large, worth the risk. Recent research has indicated that, while there is a general
relationship between brain size and IQ, it's the number of connections within your brain that
count.

For example, if you were to read all of the entries in this website, and then understand the
connections and relationships between them, your brain would grow more complex to accomodate
your new knowledge. What are you waiting for?

Compare to the electro-culturer from The Ancient Brain (1929) by A.G. Stangland.